1. Field of the Invention
The present invention relates to a printing control apparatus capable of conducting two-sided printing on a print sheet by reversing feed direction thereof, and in particular, relates to a printing control apparatus in which print condition including print order and print direction of image extended over two pages can be set according to kinds of print sheet, thereby it can conduct two-sided printing in various manners.
2. Description of Related Art
Conventionally, it is proposed various printing apparatuses such as laser printer capable of conducting both single-sided printing and two-sided printing. In these printing apparatuses, various manners to enable the two-sided printing are adopted. For instance, it is known a manner in which the two-sided printing is realized by reversing feed direction of the print sheet, thereby inside and outside of the print sheet are reversed, in order to efficiently reduce space and cost of the printing apparatus.
For example, in the laser printer, the two-sided printing is conducted as follows. That is, after image printing is done on the first plane of the print sheet it is fed to a predetermined reversing position and feed direction thereof is reversed at the reversing position, thereby the rear end of the print sheet after image is printed on the first plane reversely becomes the front end along the reversed feed direction. And when the print sheet is fed to a print part including a photosensitive drum, the second plane of the print sheet opposes to the photosensitive drum and image printing is conducted on the second plane.
And in the above laser printer, the two-sided printing is done on the print sheet so that printing directions in both single-sided printing mode and two-sided printing mode mutually coincide. Here, concretely, in case of the single-sided printing mode, image is printed on the fed print sheet according to the same direction as the feed direction thereof. On the other hand, in case of the two-sided printing mode, image is first printed on the first plane under a condition that print format is rotated 180.degree. (degrees) against the feed direction of the print sheet and further image is printed on the second plane according to the same direction as the feed direction thereof, similar to the case of the single-sided printing mode.
However, there remain following problems in the above printer that the two-sided printing is conducted by reversing the feed direction of the print sheet. That is, in the two-sided printing mode, after image printing is conducted on the second plane of the print sheet continuous to image printing of the first plane, the print sheet is fed out to a sheet discharge tray. At that time, the print sheet is stacked on the sheet discharge tray so that the second plane on which image printing is lately conducted becomes under plane. But, in case that image is printed over several pages, page number printed on the print sheet cannot become serial number because the print sheets are stacked on the sheet discharge tray one by one under a condition that the second plane on which content of the second page is printed become under planes. Therefore, it is necessary for a user to rearrange the print sheets in good order after printing is completed and such rearrangement is very troublesome.
Here, there is no problem in the above printer when image is printed on a white print sheet since there is no distinction of inside and outside, top and bottom in the print sheet. But, there will occur a problem that the print sheet is reversed in case of two-sided printing when a kind of print sheet having pre-prints thereon by which print direction is predetermined, is used.
For instance, in case that the print sheet having company name printed thereon is utilized and such print sheet is arranged in a sheet supply cassette so that the upper end thereof coincides with the top end of feed direction according to the single-sided printing mode, there will be no problem in printing under the single-sided printing mode. However, in case of the two-sided printing mode, image is printed after the print format is rotated 180.degree. when image printing is conducted on the first plane of the print sheet, thereby there will occur a case that printing directions of the company name and the printed content do not coincide with each other, as a result, both the company name and the printed content are arranged on the print sheet in a condition that reading directions thereof become different from each other.
In order to dissolve the above problems, it is conceivable that the sheet supply cassette is independently arranged for each of the single-sided printing mode and the two-sided printing mode. However, in this case, there will arise a new problem that it is very troublesome for a user of the printer. At that time, it is understandable that the company name and the printed content are put in order if the feed direction of the print sheet having pre-prints thereon is reversed in the two-sided printing mode.